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91.
深水网箱投饵机设计与试验研究   总被引:15,自引:0,他引:15  
根据网箱养殖的特点,结合网箱养殖的经验,设计了1种深水网箱投饵机,并进行了相应的试验,测定了不同情况下产生的真空度以及在冲饵管和吸饵管不同开度时的下料时间。此投饵机使用水力环流供饵、水力抽负吸饵、水动力投饵,充分利用了丰富的海水资源,用汽油机水泵作动力,利用管道将饵料抛向网箱,可向多个、距离不同的网箱供饵。作为1种新的投饵机具,可用于网箱养鱼和池塘养鱼的投饵。  相似文献   
92.
两参量的海面阻力系数模式的探讨   总被引:4,自引:0,他引:4  
汪炳祥 《海洋与湖沼》1997,28(1):96-103
从风浪的能量平衡方程出发,引进若干风要素与波要素以及波要素之间的定性关系,经演算可导出海面阻力系数(Cp)或是风速(U)和波龄(β)或是U和波高(H)的函数,然后沿用最小二乘法,终将得出4组12个回归方程。当β(或β)或H为某一给定值,惟有U为唯一参量时,所提各式均可简化为非线性方程:CD=a+b,U+c.U^2;式中a,b和c为三个经验系数,就所检验的例子而言,本文的结果与实际的符合前人的为好。  相似文献   
93.
塘沽海区海底地形的SAR影像仿真与反演研究   总被引:1,自引:0,他引:1  
利用袁业立、金梅兵(1997)提出的海底地形SAR影像仿真与反演模型,对渤海塘沽海区的一张Radarsat SAR影像进行了仿真和水深反演研究。研究结果表明:仿真影像与真实SAR影像基本吻合,反演水深与实际水深也有较好的一致性;进一步证实了袁业立(1997)SAR成像机理的正确性和在中国近海利用SAR影像进行浅海水深探测的可行性。  相似文献   
94.
It is important to estimate hard-to-observe parameters in the ocean interior from easy-to-observe parameters. This study therefore demostrates a reconstruction of observed temperature and salinity profiles of the sea east of Japan (30°≈40°N, 140°≈150°E). The reconstruction was done by estimating suboptimal state from several values of the observed profiles and/or sea surface dynamic height (SDH) calculated from the profiles. The estimation used a variational method with vertical coupled temperature-salinity empirical orthogonal function (EOF) modes. Profiles of temperature and salinity in the subtropical region are effectively reconstructed from in situ temperature profile data, or sea surface temperature (SST) and SDH. For example, the analyzed temperature field from SST and SDH has an accuracy to within 1°C in the subtropical region. Salinity in the sea north of Kuroshio, however, is difficult to estimate because of its complex variability which is less correlated with temperature than in the subtropical region. Sea surface salinity is useful to estimate the subsurface structure. We also show the possibility that the estimation is improved by considering nonlinearity in the equation calculating SDH from temperature and salinity analysis values in order to examine the misfit between analysis and observation. Analysis using TOPEX/POSEIDON altimetry data instead of SDH was also performed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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As part of the Vertical Offshore Reference Frames (VORF) project sponsored by the U. K. Hydrographic Office, a new model for Sea Surface Topography (SST) around the British Isles has been developed. For offshore areas (greater than 30 km from the coast), this model is largely derived from satellite altimetry. However, its accuracy and level of detail have been enhanced in coastal areas by the inclusion of not only the 60 PSMSL tide gauges with long-term records around the coasts of the United Kingdom and Ireland but also some 385 gauges established at different epochs and for different observation spans by the U. K. Admiralty. All tide gauge data were brought into a common reference frame by a combination of datum models and direct GPS observations, but a more significant challenge was to bring all short-term sea level observations to an unbiased value at a common epoch. This was achieved through developing a spatial-temporal correlation model for the variations in mean sea level around the British Isles, which in turn meant that gauges with long-term observation spans could be used as control points to improve the accuracy of Admiralty gauges. It is demonstrated that the latter can contribute point observations of mean sea level (MSL) with a precision of 0.078 m. A combination of least squares collocation and interpolation was developed to merge the coastal point and offshore gridded data sets, with particular algorithms having to be developed for different configurations of coastal topology. The resulting model of sea surface topography is shown to present a smooth transition from inshore coastal areas to offshore zones. Further benefits of the techniques developed include an enhanced methodology for detecting datum discontinuities at permanent tide gauges.  相似文献   
97.
In the summers of 1999 and 2003, the 1st and 2nd Chinese National Arctic Research Expeditions measured the partial pressure of CO2 in the air and surface waters (pCO2) of the Bering Sea and the western Arctic Ocean. The lowest pCO2 values were found in continental shelf waters, increased values over the Bering Sea shelf slope, and the highest values in the waters of the Bering Abyssal Plain (BAP) and the Canadian Basin. These differences arise from a combination of various source waters, biological uptake, and seasonal warming. The Chukchi Sea was found to be a carbon dioxide sink, a result of the increased open water due to rapid sea-ice melting, high primary production over the shelf and in marginal ice zones (MIZ), and transport of low pCO2 waters from the Bering Sea. As a consequence of differences in inflow water masses, relatively low pCO2 concentrations occurred in the Anadyr waters that dominate the western Bering Strait, and relatively high values in the waters of the Alaskan Coastal Current (ACC) in the eastern strait. The generally lower pCO2 values found in mid-August compared to at the end of July in the Bering Strait region (66–69°N) are attributed to the presence of phytoplankton blooms. In August, higher pCO2 than in July between 68.5 and 69°N along 169°W was associated with higher sea-surface temperatures (SST), possibly as an influence of the ACC. In August in the MIZ, pCO2 was observed to increase along with the temperature, indicating that SST plays an important role when the pack ice melts and recedes.  相似文献   
98.
黑潮延伸区的海平面异常和中尺度涡的统计分析   总被引:4,自引:0,他引:4  
利用1993~2004年卫星高度计TP/Jason-1和 ERS/ENVISAT提供的海平面异常(SLA)融合数据,分析了黑潮延伸区12年来的平均海平面异常的变化特征及中尺度涡的分布规律.研究表明,在黑潮延伸区海平面异常(SLA)呈递增趋势,年平均上升率为8.89mm/a,显著性周期是1年、0.5年和6年;黑潮延伸区的海平面异常和海表面温度异常的低频分量与Nino3指数具有较高的相关性.这说明,黑潮延伸区的海平面变化和海表面温度与厄尔尼诺事件密切相关,都受到黑潮变化的密切影响.在日本东部的黑潮延伸区,中尺度涡自东向西移动,寿命约为1年,移动速度大约是10经度/年.气旋涡和反气旋涡的面积呈现几乎同步增减的规律,均呈年周期变化,上半年少,下半年多.在1997~1998年,黑潮延伸区内中尺度涡的面积显著减小,并且正好对应于Nino3指数极大值出现的年份.因此,黑潮延伸区内中尺度涡的数量和强度也与厄尔尼诺事件密切相关.  相似文献   
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